Shotshells typically include a tubular body with a primer at one end, a propellant powder ignited by the primer, and a payload such as a series of shot pellets or a slug in front of the propellant powder. Such shotshells further typically include a shotshell wad between the propellant powder and the payload for containing the payload as it moves down barrel after firing. For example, FIG. 1A illustrates one type of conventional shotshell wad, here shown as Remington Arms Company, Inc. Model TGT12S Shotshell Wad, while FIG. 1B illustrates an additional embodiment of a conventional shotshell wad having an elongated tubular body with a series of petals or split sections that flare outwardly after firing and define a cup for containing the payload. Conventional shotshell cartridges have, however, reached a performance plateau wherein the maximum velocity for a given payload generally is restricted by the standard operating pressure limits set forth in the Sporting Arms and Ammunition Manufacturers Institute, Inc. (“SAAMI”) guidelines for a given gauge and length. Such performance limitations have been observed in particular with steel loads required for use while hunting waterfowl and other similar game. Steel loads have an inherent disadvantage in performance properties resulting from the decreased density of the steel material versus similar size lead shot/loads. A lead pellet of equal size to its steel counterpart generally will contain more energy when fired at an equal velocity because its density and therefore mass will be greater. This handicap in energy levels for a given pellet size typically requires that a steel load use larger diameter pellets to ensure reasonable energy levels for game harvesting, and in doing so significantly lowers the number or volume of pellets a payload can contain, which in turn limits or hampers the effectiveness of the shotshell in use, particularly for game harvesting.
Accordingly, it can be seen that a need exists for a shotshell cartridge design that addresses the foregoing velocity restrictions and other related and unrelated problems.